Buy 4 steppermotors NEMA23 with 400cpr encoders. Buy 4 screwfeeders (backlash free), 6 lineair motion rails with carriages (8) make a cabinet with 2 computers a cnc-controller, 4 stepperdrivers (1600-microstep) on a wind-tunnel and a 1000W Powersupply 72V, about 200 kilo's of aluminum profile, a bag full of metal hardware , a spindlemotor etc. etc... and think out a machine... That's how you do that... at least, i did...
Kees